2021 Cummins 1075 lbft peak torque at 1356 rpm

4x4ord wrote:
^^^^ You may be right that developing peak torque down at 1356 rpm may indicate the new power curve has potential for better fuel economy. It will be interesting to see if that’s the case. But, imagine pulling a heavy high profile trailer into a stiff wind or up a slight grade were 277 hp is required, Your right foot would be through the floor board and you’re in 6th gear at 1356 rpm. I can’t imagine a 430 hp engine being programmed to ever run down at such a low rpm at full throttle when it is only capable of 277 hp at that rpm. You are probably right though, the 2021 will likely hold onto the top gears a little longer to make use of the torque at lower rpms for fuel efficiency. The big diesels in the semis do create maximum torque at very low rpm but they are still producing close to maximum power at that rpm as well. The Cummins x15 for instance can be ordered with 400 to 500 hp at an engine rpm of 1700. It has a peak torque of 1850 rpm. If that peak torque is produced at 1000 rpm the engine is still putting out up to 88% of rated power. Even with the 500 hp engine a torque rating at 1000 rpm is at about 60% of rated engine speed.... so it is a meaningful number.

An X15 economy at max tune (500 hp) makes peak torque (1850) starting at 950 rpm. That's 335 hp, or 67% of peak hp.

That's splitting hairs vs the 64.4% of peak hp the Ram makes at peak torque.

I'm willing to bet the ECU is tuned so you can achieve peak torque without commanding 100% throttle position, maybe via the cruise control. This way, it's more efficient to make 277 hp @ 1300 rpm than it is at 2000+ rpm and partial torque output.